1. Field of the Invention
The present invention relates to a hanging device with fast hooking and automatic release, particularly for lifting and conveying a container, said device being also apt to transfer to said container electric energy on two or more circuits.
A hanging device of this type can be used in particular, but not exclusively, for hooking and transporting a load with aircraft means, as particularly helicopters, or with landcraft means, when the load consists of a special container or distributor of sundry materials, wherein the distribution is operated under the control of electric pulses sent from the transport means.
2. Description of the Prior Art
A known device of this type, described for example in the Italian Pat. No. 953.239, comprises an eyelet of connection to the helicopter, having an enlarged base with a central hole, into which freely rotates a pin extending downward into a suspension hook. The hook is formed in two parts, one of which is fixedly connected to said pin, while the other rotates in respect of the first about a horizontal axis, placed in correspondence of the lowest part of the hook. Releasable locking means keep said second part of the hook raised, so as to form with the first part an essentially closed hook, which is perfectly apt to support the bracket of a load lifting sling. When desired, said locking means release said second hook part, which oscillates downward and frees said bracket.
This known device is completed by an electric circuit apt to transmit electric signals from the transport means, for instance a helicopter, towards the load, said circuit comprising:
three current feeding brushes, fixedly connected to the connection eyelet, and three slip rings, rotating with said hook support pin, in order to guarantee the feeding of current from the fixed eyelet to the rotating hook, leaving said hook totally free to rotate;
two contact blades, positioned on either side of the hook, whose contacts are apt to cooperate with conductive plates fixed on the two opposite sides of said bracket, in order to guarantee the feeding of current from the rotating hook to the bracket and then from this latter to the hanging container.
A device of this type, though working perfectly, has proved to undergo damage during use. In particular, the contact blades fixed to the hook sides are too exposed to atmospheric agents and to accidental impact, whereby, in a relatively short while, they are no longer apt to guarantee a perfect and safe electric connection, as indispensable.